Answer: The fundamental difference lies in their ability to conduct electricity. A conductor is a material with a low electrical resistance that allows electric current to flow through it easily. Metals like copper and aluminum, which are used extensively in our transmission lines, are excellent conductors. A non-conductor, or insulator, is a material with high electrical resistance that resists the flow of electric current. Materials such as porcelain, glass, and polymer composites, which we use to create insulators for our overhead transmission lines, prevent electricity from traveling to the support structures, ensuring safety and system integrity.